.TH TS2ALT 8 "March 2024" "linuxptp"
.SH NAME
tz2alt - Monitors daylight savings time changes and publishes them to PTP stack.

.SH SYNOPSIS
.B ts2alt
[
.B \-hmqv
] [
.BI \-f " conf"
] [
.BI \-k " key"
] [
.BI \-p " period"
] [
.BI \-w " window"
] [
.BI \-z " timezone"
] [
.I long-options
]
.I .\|.\|.

.SH DESCRIPTION
.B tz2alt
leverages the local time zone database to monitor for changes in
daylight savings time and publishes the pending changes to the PTP
stack.

.SH OPTIONS
.TP
.BI \-f " config"
Read configuration from the specified file.
No configuration file is read by default.
.TP
.BI \-h
Displays the command line help summary.
.TP
.BI \-l " print-level"
Sets the maximum syslog level of messages which should be printed or
sent to the system logger. The default is 6 (LOG_INFO).
.TP
.B \-m
Prints log messages to the standard output.
.TP
.B \-q
Prevents sending log messages to the system logger.
.TP
.B \-v
Prints the software version and exits.

.SH LONG OPTIONS

Each and every configuration file option (see below) may also appear
as a "long" style command line argument.  For example, the use_syslog
option may be set using either of these two forms.

.RS
\f(CW\-\-use_syslog 1   \-\-use_syslog=1\fP
.RE

Option values given on the command line override values in the global
section of the configuration file.

.SH CONFIGURATION FILE

The configuration file is divided into sections. Each section starts with a
line containing its name enclosed in brackets and it follows with settings.
Each setting is placed on a separate line, it contains the name of the
option and the value separated by whitespace characters. Empty lines and lines
starting with # are ignored.

.SH GLOBAL OPTIONS

.TP
.B active_key_id
Used in conjunction with \fBspp\fR and \fBsa_file\fR directives to
specify which key from the \fBspp\fR defined Security Association
should be used for outbound icv calculations. All Security Assocations
are read from the file specified by \fBsa_file\fR. Requires \fBspp\fR
and \fBsa_file\fR directives. Must be in the range of 1 to 2^32-1,
inclusive. The default is 0 (disabled).

.TP
.B domainNumber
The domain attribute of the local clock.
The default is 0.

.TP
.B leapfile
The path to the current leap seconds definition file. In a Debian
system this file is provided by the tzdata package and can be found at
/usr/share/zoneinfo/leap-seconds.list. If a leapfile is configured it
will be reloaded if modified. The default is an empty string, which
causes the program to use a hard coded table that reflects the known
leap seconds on the date of the software's release.

.TP
.B logging_level
The maximum logging level of messages which should be printed.
The default is 6 (LOG_INFO).

.TP
.B message_tag
The tag which is added to all messages printed to the standard output
or system log.  If the tag contains the string "{level}", it will be replaced
with the log level of the message as a number.  The default is an empty string
(which cannot be set in the configuration file as the option requires an
argument).

.TP
.B sa_file
Specifies the location of the file containing Security Associations used
for immediate security processing of the Authentication TLV in support of
the optional security mechanism defined in ieee1588-2019 ch 14.16. See
\fBSECURITY ASSOCIATION OPTIONS\fR for more info on file contents.
The default is an empty string. (disabled).

.TP
.B spp
Specifies the security parameters pointer for the desired security association
to be used for authentication tlv support. If specified, the port owning the
spp will attempt to attach (outbound) and check (inbound) authentication tlvs
for all messages in accordance to the corresponding security association
sourced via the \fBsa_file\fR directive. Not compatible with one step ports.
Must be in the range of -1 to 255, inclusive. The default is -1 (disabled).

.TP
.B transportSpecific
The transport specific field. Must be in the range 0 to 255.
The default is 0.

.TP
.B use_syslog
Print messages to the system log if enabled.  The default is 1 (enabled).

.TP
.B verbose
Print messages to the standard output if enabled.  The default is 0 (disabled).

.SH WARNING

Be cautious when sharing the same configuration file between ptp4l,
phc2sys, and tz2alt.  Keep in mind that values specified in the
configuration file take precedence over the default values.  If an
option which is common to the other programs is set in the
configuration file, then the value will be applied to all the programs
using the file, and this might not be what is expected.

It is recommended to use separate configuration files for ptp4l,
phc2sys, and tz2alt in order to avoid any unexpected behavior.

.SH SEE ALSO
.BR ptp4l (8)
